US Air Force sets speeds of Mach 6

A possible strategy to counter is in producing a really fast aircraft that could get over those countries right away as opposed to losing their spy satellites.

The US Air Force is on its way to develop airplanes that approach 6mach or more. Known as the Falcon, High Fire and Blackswift, the experiments and tests are being closely guarded, hypersonic cruise missile may be the first operational product to emerge from the research.

Teams, working with private contractors, also hope to develop long-range hypersonic aircraft that would take off from a conventional runway, travel more than 10,000 miles in two hours and make a runway landing. One of the best known military planes that approached hypersonic speeds is the now-retired Air Force SR-71 that flew at 3.2 times the speed of sound.

An experimental hypersonic craft known as the X-43A tripled that speed, flying at Mach 9.6, or nearly 7,000 miles per hour. The X-43 flights, however, were only seconds long, and scientists are trying to find ways to keep hypersonic craft airborne for long distances. Much of the current work is being directed by the Defense Advanced Research Projects Agency (DARPA), the arm of the Defense Department responsible for advancing emerging technologies for military use. The Falcon program aims at developing a reusable hypersonic cruise vehicle, HCV, capable of delivering 12,000 pounds of payload at a distance of 9,000 nautical miles, in less than two hours. DARPA offered new details of the Blackswift tests in budget documents that accompanied the release of President Bush's defense budget this week. DARPA described the Blackswift tests as "an evolution" of the reusable HCV developed under the Falcon program. The goal, said DARPA, is to eventually develop "enhanced-capability" high-speed vehicles for intelligence, surveillance, reconnaissance, and strike "or other national need missions." Lockheed Martin is doing preliminary work with DARPA on Blackswift but the program is still evolving and no contract has been issued. Lewis said the X-51 development and Blackswift are separate programs but are "clearly linked through technology."

Air Force deputy program manager for Blackswift will be stationed at the Air Force Research Laboratory near the X-51 program, he said. U.S. officials are also working with Australian researchers in what Lewis described as "an extremely sophisticated" program to delve into the fundamentals of physics involving hypersonic flights. Those tests, known as High Fire, are being carried out at an installation in the Australian Outback and will feed into the X-51 and Blackswift programs.